#测试pr
import pygame
import sys
import random
import time

# 全局定义
SCREEN_X = 600
SCREEN_Y = 600


# 蛇类
# 点以25为单位
class Snake(object):
    # 初始化各种需要的属性 [开始时默认向右/身体块x5]
    def __init__(self):
        self.dirction = pygame.K_RIGHT
        self.body = []
        for x in range(5):
            self.addnode()

    # 无论何时 都在前端增加蛇块
    def addnode(self):
        left,top = (0,0)
        if self.body:
            left,top = (self.body[0].left,self.body[0].top)
        node = pygame.Rect(left,top,25,25)
        if self.dirction == pygame.K_LEFT:
            node.left -= 25
        elif self.dirction == pygame.K_RIGHT:
            node.left += 25
        elif self.dirction == pygame.K_UP:
            node.top -= 25
        elif self.dirction == pygame.K_DOWN:
            node.top += 25
        self.body.insert(0,node)

    # 删除最后一个块
    def delnode(self):
        self.body.pop()

    # 死亡判断
    def isdead(self):
        # 吃没了
        if len(self.body) ==0 :
             return True
        # 撞墙
        if self.body[0].x  not in range(SCREEN_X):
            return True
        if self.body[0].y  not in range(SCREEN_Y):
            return True
        # 撞自己
        if self.body[0] in self.body[1:]:
            return True
        return False

    # 移动！
    def move(self):
        self.addnode()
        self.delnode()

    # 改变方向 但是左右、上下不能被逆向改变
    def changedirection(self,curkey):
        LR = [pygame.K_LEFT,pygame.K_RIGHT]
        UD = [pygame.K_UP,pygame.K_DOWN]
        if curkey in LR+UD:
            if (curkey in LR) and (self.dirction in LR):
                return
            if (curkey in UD) and (self.dirction in UD):
                return
            self.dirction = curkey


# 食物类
# 方法： 放置/移除
# 点以25为单位
class Food:
    def __init__(self):
        self.rect = pygame.Rect(-25,0,25,25)

    def remove(self):
        self.rect.x=-25

    def set(self):
        if self.rect.x == -25:
            allpos = []
            # 不靠墙太近 25 ~ SCREEN_X-25 之间
            for pos in range(25,SCREEN_X-25,25):
                allpos.append(pos)
            self.rect.left = random.choice(allpos)
            self.rect.top  = random.choice(allpos)
            #print(self.rect)


class BigFood:
    def __init__(self):
            self.rect = pygame.Rect(-25,0,25,25)
    def remove(self):
        self.rect.x=-25
    def set(self):
        if self.rect.x == -25:
            allpos = []
            # 不靠墙太近 25 ~ SCREEN_X-25 之间
            for pos in range(25,SCREEN_X-25,25):
                allpos.append(pos)
            self.rect.left = random.choice(allpos)
            self.rect.top  = random.choice(allpos)
            #print(self.rect)

# 显示文字
def show_text(screen, pos, text, color, font_bold = False, font_size = 60, font_italic = False):
    #获取系统字体，并设置文字大小
    cur_font = pygame.font.SysFont("宋体", font_size)
    #设置是否加粗属性
    cur_font.set_bold(font_bold)
    #设置是否斜体属性
    cur_font.set_italic(font_italic)
    #设置文字内容
    text_fmt = cur_font.render(text, 1, color)
    #绘制文字
    screen.blit(text_fmt, pos)

# 画背景
def show_background(screen):
    background=pygame.image.load(r"images/1.png")
    bgx = 0
    bgy = 0
    while True:
        screen.blit(background,(bgx,bgy))
        if bgx <= SCREEN_X-30:
             if bgy <= SCREEN_Y-30:
                bgx += 30
             else:
                break
        else:
             bgx = 0
             bgy += 30


def main():
    pygame.init()
    screen_size = (SCREEN_X,SCREEN_Y)
    screen = pygame.display.set_mode(screen_size)
    show_background(screen)
    pygame.display.set_caption('Snake')
    clock = pygame.time.Clock()
    scores = 0
    isdead = False
    # 蛇/食物
    snake = Snake()
    food = Food()
    big_food = BigFood()

    while True:
        for event in pygame.event.get():
            if event.type == pygame.QUIT:
                sys.exit()
            if event.type == pygame.KEYDOWN:
                snake.changedirection(event.key)
                # 死后按space重新
                if event.key == pygame.K_SPACE and isdead:
                    return main()

        #渲染背景图
        show_background(screen)
        # 画蛇身
        if not isdead:
            snake.move()
        for rect in snake.body:
            if snake.body.index(rect):
                snake_color = random.randint(0,255)
                pygame.draw.rect(screen,(snake_color,snake_color,snake_color),rect,0)
            else:
                if snake.dirction == pygame.K_LEFT:
                 if not isdead:
                     snake_img = pygame.image.load(r"images/head_left.png")
                elif snake.dirction == pygame.K_RIGHT:
                 if not isdead:
                     snake_img = pygame.image.load(r"images/head_right.png")
                elif snake.dirction == pygame.K_UP:
                 if not isdead:
                     snake_img = pygame.image.load(r"images/head.png")
                elif snake.dirction == pygame.K_DOWN:
                 if not isdead:
                     snake_img = pygame.image.load(r"images/head_up.png")
                screen.blit(snake_img,rect)

        # 显示死亡文字
        isdead = snake.isdead()
        if isdead:
            show_text(screen,(100,200),'YOU DEAD!',(227,29,18),False,100)
            show_text(screen,(150,260),'press space to try again...',(0,0,22),False,30)
        # 当食物rect与蛇头重合,吃掉 -> Snake增加一个Node
        if food.rect == snake.body[0]:
            food.remove()
            snake.addnode()

        # 食物投递
        food.set()
        food_img = pygame.image.load(r"images/ls.png")
        screen.blit(food_img,food.rect)
        #pygame.draw.rect(screen,(136,0,21),food.rect,0)

        if big_food.rect == snake.body[0]:
            #screen.fill((0,0,0))
            big_food.remove()
            if len(snake.body)> 0:
                if random.randint(1,10) > 5:
                  for x in range(random.randint(1,10)):
                       snake.addnode()
                else:
                  if len(snake.body)> 0:
                     for x in range(random.randint(1,len(snake.body))):
                         snake.delnode()
                     snake.addnode()
        # 大食物
        big_food.set()
        big_food_img = pygame.image.load(r"images/cw.png")
        screen.blit(big_food_img,big_food.rect)

        pygame.display.update()
        clock.tick(10)


if __name__ == '__main__':
    main()
